Various vehicles such as aircraft need the capability to permit the rapid removal and/or addition of cargo and/or passenger seats. Such vehicles also need the capability of permitting the rapid repositioning of seats and/or cargo within the vehicle. These needs are particularly required in passenger and cargo type aircraft.
These requirements are commonly met by providing a number of locking tracks which run lengthwise in the floor of the aircraft. These locking tracks commonly have a slot which would generally run the entire length of the locking track. Semi-circular cut out portions would generally extend outward from the slot and are generally located at equally spaced distances along the locking tracks. These semi-circular cut out portions would also be interconnected by a smaller slot which runs lengthwise in the upper surface in the locking track. The purpose of the slot and cut out portions is to receive portions of track fasteners which would be used to secure cargo and/or passenger seats to the locking tracks. Through the use of such track fasteners in the locking tracks, it is easy to remove and/or add cargo and/or passenger seats to or from the aircraft. In a similar manner the locking tracks and associated track fasteners permit passenger seats and/or cargo to be rapidly repositioned within the aircraft.
Also such locking tracks and associated track fasteners have worked out reasonably satisfactory. In terms of normal use they have had certain deficiencies in terms of adequately securing aircraft seats and possibly cargo to the floor of the aircraft when the aircraft is subject to rapid deacceleration which would occur when the aircraft is subjected to a crash. In these instances rather high forces are exerted on the track fasteners and the associated portions of the locking tracks to which the track fasteners are connected. In some instances the track fasteners have actually been pulled loose from the locking tracks. This has resulted in the passenger seat becoming loose from the floor of the aircraft and being propelled within the aircraft which greatly increases the chances of injury or death to the occupants of that seat or other occupants in the aircraft.
Consequently a need exists to insure that the track fasteners remained secured to the associated locking tracks when the aircraft is subjected to a crash. Unfortunately, it has been determined that in many instances it is the failure of the locking track that results in the track fastener becoming loose from the associated locking track. In particular it has been determined that the upper portion of the locking track, including the narrow slot, spreads apart due to the upward exerting forces upon the track fasteners and this results in the release of the track fasteners. One possible solution for this problem might be to attempt to strengthen the locking tracks themselves; however, even if such a solution was possible this would require the retro fitting of many existing aircraft.
This invention overcomes the problem associated with the present locking tracks and associated track fasteners. In addition this invention does not require any change to the existing locking tracks. This invention provides a track fastener which in addition to performing its normal locking function to secure the track fastener to the locking tracks also prevents an adjacent portion of the locking track from spreading apart to permit release of the track fasteners.